Starting device for internal-combustion engines



' I I 1,622289. *M f'h s 2 I v. a. NELSON STARTING DEVICE FOR INTERNAL COMBQS fTION ENGINES Filed my 1-1. 192.4

Patented Mar. 29, 1927.

VICTOR B. NELSON ,-OF ROCKFORD, ILLINOIS.

, srnnrrme nnvion ron INTERNAL-COMBUSTION ENGINES.

' Application filed July 11, 1924. Serial No. 725,327.

This invention relates to devices for starting internal combustion engines from a condition of rest and hasniore particular reference to manually operated devices for this purpose. Devices of this kind are especially adapted for starting small engines, either stationary or portable. My invention, however, is not limited to the use of manual force as the impelling power but might be employed with other forms of motor power, as will be apparent hereinafter.

The purpose vof my invention is to provide a simple and improved starting device employing a spirally wound element which when unwound by a constant pull and constant motion willimpart uniformly accelerating rotary motion to the crank-shaft of the engine. If the impelling motion is varied or accelerates, the rotary motion imparted to the crank-shaft will be proportionally accelerated. A

My invention .is applied in a practical i manner as disclosed herein, to the flywheel of a small portable engine of the kind used for propelling canoes, rowboats and the like. Inthis embodiment I have provided a conical body on a flywheel having a spiral groove in its periphery, inwhich groove a rope or cord is adapted to be wound after having been detachably fastened to the smaller end of the conical body so that when the free end of the rope is pulled steadily in a constant lineal motion, uniformly accelerating rotary motion will be imparted to the flywheel, or if the impelling motion is accelerated the flywheel motion will be pro portionally accelerated. This is especially advantageous because a greater number of complete revolutions will be imparted for a given length of groove than with helical grooves or such as are provided on a cylindrical body and, furthermore,. because the 'acceler'ating'niotion brings the speed closer to the normal engine speed, constantly fawhen unwound in the manner described. It

flywheel as it is shown in Fig. 1.

.In the present embodiment of myinvention .the starting device is applied directly to the flywheel of an internal combustion Fig. 2, is a top view of said device and the engine ofthe portable type adapted for propelling small boats. As shown in Fig. 1 this is an opposed double cylinder engine designated generally by 3, the crank-shaft 4; of which is on a vertical axis and the flywheel 5 is fixed to the upper end of the crank-shaft. v

My improved starting device consists in this en'ibodiinent of a frusto-conical body or plate designatedsuitable means such as screws to the upper side of the flywheel coaxial therewith. In the periphery of this body is formed a spiral groove designated by 8 which winds about and rises on said body so that the smallest convolution terminates at the upper base thereof, at which point the body is recessed to provide a hook 9. A suitable rope or cord, provided at one end with a knot which may be engaged in the recess of the hook, or a loop which may be engaged over the ice.

generally by 6 fixed by clockwise direction, viewing Fig. 2 so as to emanate tangentially from the lowermost convolution. When this end of the rope is pulled evenly in a constant motion the flywheel will be turned in a uniformly accelerating motion. If the pull onv the rope is varied to increase the speed, the motion imparted to the flywheel will be correspondingly and proportionally incieased'at the accelerating ratio. The end of the rope fastened to the hook 9 will automatically release therefrom when the innermost end of the grove is reached. This provides a very effective starting device for reasons explained above. I

In the present application I have illustiated but a single working embodiment of my invention, the essential feature of which is the use of a starting element connected to an engine crankshaft and'winding about an axis and rising in a cone so as to impart accelerating motion to the crank-shaft should be understood therefore that my inin combination, the

groove in its periphery,the convolutions of the groove decreasing in diameter toward the smaller base of said body, and means for releasably attaching a rope or cord to the body at the inner end of the groove, whereby said rope after having been wound in said groove may be pulled for imparting accelerating rotary motion to the crank shaft.

whereby a rope attached to the body and wound in said groove may be pulled at its free end for-imparting rotary motion to the.

body, the convolutions at the end of the groove at which the-rope is attached to the being of less radius than that at the oppbslte end of the groove at which the motion is'initiated, whereby greater leverage is ob tained impartlng the initial rotary motion connecting a ropeor cord thereto,

and said motion will be accelerated with constant lineal pullof the rope.

3. In a device of the character described, the combination of a shaft to be spun, a rope for spinning theshaft. and a device 'for proriding a detachable driving connection between said rope and said shaft, having said rope wound thereon from a point on a small v radius through a number of turns to a point on a comparatively large radius. to afford greater leverage in starting from rest and decreasing leverage after starting.

4. In a device of the character described, the combination of a shaft to be spun, a rope for spinning the shaft and a pulley provid- '4 ing a detachabledriving connection between said rope and said shaft, said pulley-having a periphery for winding said rope thereon which starts with a point on a small radius and extends to a point on a comparatively large radius to afford greater'leverage'in starting from rest as the rope is unwound and decreasing leverage after starting.

VICTOR B. NELSON. 

